Proppen (Controlling benthic release of phosphorus in different Baltic Sea scales) is a joint Nordic three-year research project. It aims to show whether pumping of oxygen-rich surface water down to the bottom-near water layers can improve the state of coastal waters that suffer from oxygen depletion. Neri is responsible for the valuation of water quality improvements expected from the oxygenation as well as for a risk perception survey of oxygenation pumping in the Baltic Sea as part of the cost-benefit analysis of the project. Surveys will take place in Sweden, Finland and Lithuania.